(1) Field of the Invention
The present invention generally relates to a virtual space communication system in which users of a plurality of computers connected via a network communicate (by voice and/or text) with each other in a virtual space shared by the computers, and more particularly to a virtual space communication system in which graphical objects (e.g., named as an xe2x80x9cavatarxe2x80x9d) acting in the virtual space shared by a plurality of computers, in accordance with operations by users, are used so that the users communicate with each other via actions of the graphical objects.
(2) Description of the Related Art
Conventionally, the so-called virtual space communication system in which users of a plurality of computers, connected by a network, communicate with each other in a virtual space shared by the computers, has been proposed. This type of system is formed as shown in FIG. 1.
Referring to FIG. 1, computers 3(1) and 3(2) (hereinafter referred to as clients) which are used by users to communicate with each other in a virtual space are connected to a network. The network is connected with an object data server 1 (e.g., a WWW server) for supplying information regarding the virtual space and a communication server 2. The communication server 2 relays communication among the clients 3(1) and 3(2) and the object data server 1.
The information regarding the virtual space which should be supplied by the object data server 1 includes files (e.g., VRML) in which the virtual space (towns, rooms, parks and the like) are described and image data (CG data). The files in which the virtual space is described include information regarding attributes (positions, shapes, colors and the like) of objects forming the virtual space (existing in the virtual space).
In each of the clients 3(1) and 3(2) into which the information regarding the virtual space supplied from the object data server 1 via the network is down loaded, the same image of the virtual space is displayed. That is, the same virtual space is shared by the respective clients 3(1) and 3(2). Graphical objects, for example, named xe2x80x9cavatarsxe2x80x9d, which are assigned to the clients are displayed in the virtual space. The xe2x80x9cavatarsxe2x80x9d act (move and/or speak) based on operations by users in the corresponding clients. The communication server 2 manages clients which access (share) the same virtual space so that data (positions, actions and the like) regarding the xe2x80x9cavatarsxe2x80x9d and conversation sentences (character strings, voice and the like) which are input by operations in each client are transmitted to other clients via the communication server 2. As described above, the users of the respective clients communicate with each other via xe2x80x9cavatarsxe2x80x9d in the virtual space shared by the clients.
Such a system may have a function for changing the attributes (positions, shapes, colors and the like) of the objects forming the virtual space based on operations in the clients. In this case, when a position of an object is changed in the client 3(1) as shown in FIG. 2 (for example, when a vehicle his moved in the virtual space), position change information of the object is supplied to the other client 3(i)sharing the virtual space via the communication server 2. Thus, in the other client 3(i), the position of the object is changed in the same manner as in the client 3(1) (the vehicle is moved in the virtual space).
In the system in which the attributes of the objects in the virtual space can be changed, for example, after the attribute of the object is changed in the clients 3(1) and 3(i), the other client 3(2) may access the virtual space, as shown in FIG. 2. In such a case, although the attribute of the object has been changed, information regarding the virtual space in which the attribute of the object has not yet changed is down loaded from the object server 1 into the other client 3(2). Thus, the virtual space shared by the clients 3(1) and 3(i)differs from that accessed by the other client 3(2).
Accordingly, a general object of the present invention is to provide a novel and useful virtual space communication system in which the disadvantages of the aforementioned prior art are eliminated.
A specific object of the present invention is to provide a virtual space communication system in which after the attribute of the object in the shared virtual communication is changed, another user can always participate in the communication using the virtual space in which the attribute of the object has been changed.
The above objects of the present invention are achieved by a virtual space communication system comprising: a virtual space management computer which manages information regarding a virtual space; a plurality of client computers each of which receives information regarding the virtual space from the virtual space management computer and generates communication information used in the virtual space, each of the plurality of client computers having object state changing means for changing a state of an object included in the virtual space; and a communication management computer which intermediates communications regarding communication information and information representing change of a state of an object among the plurality of client computers sharing the virtual space, wherein the virtual space communication system further comprises changing means for, when a state of an object changed in one of the plurality of client computers, changing information of the virtual space managed by the virtual space management computer based on a changed state of the object.
In the system according to the present invention as described above, when the state of an object is changed in one of the plurality of client computers, the change of the state of the object is reflected on the information regarding the virtual space managed by the virtual space management computer. Thus, in a client computer which receives the information regarding the virtual space from the virtual space management computer after the state of the object is changed, communication information can be generated in the virtual space including the object whose state has been changed. That is, according to the present invention, another user can always join the virtual space on which the state of the object having the changed attribute is reflected after the attribute of the object is changed.
The object is an element of the virtual space. The state of the object may include attributes regarding the state, such as a position in the virtual space, a shape, a color and the like.
The communication information may include various kinds of information, such as graphical images (an object named as an avatar), conversation scripts and voices, communicated among the client computers.
In order to be able to directly change the information regarding the virtual space, the above system may be formed so that the changing means has change informing means for informing the virtual space management computer of state change information indicating that a state of an object has been changed in one of the plurality of client computers, and virtual space changing means, provided in the virtual space management computer, for changing the information regarding the virtual space based on the state change information.
In this system, the virtual space management computer is directly informed of the state of the object which has been changed in one of the plurality of client computers. In the virtual space management computer, the information of the virtual space managed thereby is then changed.
In order to be able to easily change the information regarding the virtual space in the virtual space management computer, the above system may be formed so that the virtual space management computer has an object state table indicating states of respective objects forming the virtual space, and wherein the virtual space changing means has table rewriting means for rewriting the state of an object in the object state table based on the informed state change information.
In this system, due to rewriting the object state table in the virtual space management computer, the information regarding the virtual space can be changed.
In order to be able to accurately reflect information of the changed object on the information regarding the virtual space in a case where there is a plurality of computers which are suppliers of the information regarding the virtual space, the above system may be formed so that the virtual space management computer is formed of a plurality of management computers, the virtual space communication system further comprising means for managing a relationship between objects and the plurality of management computers which manage virtual spaces including the objects, wherein when the state of an object is changed in one of the plurality of client computers, information regarding a virtual space managed by a management computer being changed, the management computer, corresponding to the object whose state is changed, being decided based on the relationship managed by the means.
In this system, when the state of the object is changed in one of the plurality of client computers, a management computer which manages a virtual space including the changed object can be easily identified. The information regarding the virtual space managed by the identified management computer is then changed.
In order to able to efficiently inform the management computer, managing the virtual space including the changed object, of the change of information, the above system may be formed so that the means for managing the relationship between the objects and the plurality of management computers which manage the virtual spaces is provided in the communication management computer, wherein when the communication management computer receives from one of the plurality of client computers information indicating that the state of the client has been changed, the communication management computer informs the management computer, based on the relationship managed by the means, that the state of the object has been changed.
In this system, when the state of the object is changed in one of the plurality of client computers, other client computers are informed of this matter via the communication management computer. Thus, even if the one of the plurality of client computer does not inform other systems of the change of the state of the object, the communication management computer informs a corresponding management computer of the change of the state of the object.
In order to be able to always obtain at any time the information regarding the virtual space in which objects have been changed, the above system may be formed so as to include change informing means for, after the information regarding the virtual space managed by the virtual space management computer is changed, informing all client computers, sharing the virtual space, of the changed information.
In this system, the information regarding the virtual space which has been changed is always supplied to the client computers sharing the virtual space.
In order to be able to assign identification information which is unique in the system to an object generated in one of the plurality of client computers, the above system may further comprise identification information generating means for generating identification information identifying an object when the object is generated in one of the plurality of client computers, the identification information being unique in the system.
In order to be able to allow only a user having authority to change the state of the object, the above system may further comprise means for managing users having authorities based on which of the respective objects forming the virtual space is changed; and means for, when one of the plurality of client computers requests to change an object, determining whether a user of the one of the plurality of client computers is identical to a user who is managed by the means as a user having an authority to change the object, wherein when both the users are identical to each other, the information regarding the virtual space managed by the virtual space management computer is changed.